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VOCl3 and TiCl4 exhibit a similarity of various thermal properties, causing difficulty for these components separation through distillation technique. Dynamic behavior of distillation process of VOCl3-TiCl4 mixture was modeled based on the mass and energy balances, revealing in a model form of the ordinary differential equations. Influences of heating power, airflow, initial concentration, and operating pressure were considered. Simulation results show an ineffective distillation of the mixture under natural pressure. However, the reduction of the operating pressure advanced the pure TiCl4 recovery performance. Compared to experimental data, the relative error of the simulation findings is less than 5%, indicating the potential of the application of the proposed model for describing the distillation of the VOCl3-TiCl4 mixture.

Researchers have documented the negative effects of refractory chemicals and emergent pollutants in landfill leachate (LL) that cannot be degraded using conventional methods. The propagation, invasion, and deleterious effects of several LL hazards affect aquatic species, the environment, and food outlets, causing significant safety issues. These include cancer risks, chronic exposure, and reproductive consequences. Alternatively, solar energy is a sustainable solution for treating landfill leachate to benefit humans and the environment. In this work, a thorough bibliometric and systematic analysis of studies that employed solar energy for landfill leachate remediation over the past decade was conducted in order to determine trends, and future research areas. In addition to the energy demand, the economic aspect and the advantages of using solar power to treat landfill leachate were discussed. Additionally, the study gives specific suggestions for future research purposes and important problems. The reviewed literature revealed that combining solar-based physical-chemical and biological processes has proven to be the most efficient method for landfill leachate degradation. It also appears from the bibliometric study that more collaboration and contribution are needed to develop solar-based landfill leachate treatment. This study concludes that solar-powered landfill leachate remediation techniques would considerably increase the effectiveness of treated leachate reutilization, advancing the cause of environmental sustainability.

Laparoscopic cholecystectomy becomes standard technique for management symptomatic cholelithiasis, polype. The risk of bile duct injury following laparoscopic cholecystectomy is higher than open cholecystectomy. Purpose: To diagnosis the type of injury bile duct and management bile duct injuries sustained by laparoscopic cholecystectomy. Patients and Methods: Retrospective analyses of the patients undergoing laparoscopic cholecystectomy from 01/1999 to 06/2020. We evaluated the data according to outcome measures, characteristics and treatment results of major bile duct injuries after laparoscopic cholecystectomy. Results: We found 21 patients with major bile duct injuries sustained by laparoscopic cholecystectomy. Only 23.8% of injuries are recognized during operation. Type of injuries include: Lateral injury of common bilde duct were 4 cases, transection of bile duct were 4 cases. Management injuries include: bile duct suture were 4 cases (19.1%), hepaticojejunostomy were 10 cases (47.6%), choledochojejunostomy were 6 cases (28.5%). Conclusion: Common bile duct injury is a rare complication of laparoscopic cholecystectomy (0.35%). Immediate recognition and repair are associated with improved outcome. The optimal management depends on the timing of recognition of injury, the type, extent of bile duct injury, the patient’s conditions and the availability of experienced hepatobiliary surgeons.

The international issue to be addressed towards realizing a low-carbon society is to reduce the amount of carbon-based underground reserves such as coal, petroleum, and coke, and strongly encouraged to use carbon neutral biomass-derived resources. Woodceramics is a hybrid porous carbon material composed of wood-based biomass and phenolic resin, characterized by high far-infrared emissivity and large specific surface area. Woodceramics has been studied as heating elements and humidity and gas sensors, etc. If this is applied to the inner walls of aging and grain drying furnaces for vegetables and fruits, both ripening and drying are greatly promoted and fossil fuels used in boilers can be significantly reduced. In fact, it can produce black garlic with far infrared rays using a woodceramics brick efficiently. Furthermore, as a substitute for phenolic resin, if plant-based liquefied materials from cashew nut shell oil can be prepared and can be used for manufacturing woodceramics, then all carbon neutral circulating woodceramics made from wood-based biomass is possible to manufacture. On the other hand, woodplastics is a composite material that can be made of wooden materials and plastics, and able to expect the effective use of wood-based biomass and waste plastics.

Activated carbon produced from agricultural products and wastes has been applied widely to remove pollutants in the field of waste water treatment. However, the cost of this adsorbent depends so much on the raw material sources. Therefore, the approach of producing activated carbon from agricultural waste is strongly recommended due to economic advantages and environmental protection. One of the potential feed-stocks for the activated carbon production is cashew nut shell (CNS) waste which could reduce the negative impacts to the environment from the cashew nut processing industry and simultaneously enhance the values of the related products. This study focused on evaluating the influences of variable factors, such as activation temperature and time, on the properties of the activated carbon obtained from CNS. Methylene blue (MB) adsorption was applied to understand the adsorption mechanism of the products. The results show that increasing the activation temperature led to a rise in the adsorption capacity of the activated carbon within the temperature range of 800 to 850 °C. Otherwise, the values were reduced when the temperature was greater than 850 °C and this was related to the thermal decomposition of carbon. The adsorption capacity also increased when the activation time was changed from 30 min to 50 min. However, in the activation time range from 50 to 70 min, there was a reduction of the adsorption capacity of CNS-based activated carbon. The results also show that the MB adsorption of the activated carbon occurred with one-site-occupancy in the first layer and then layer-by-layer adsorption formation.

Background: Achalasia is a primary motor disorder of the esophagus characterized by insufficient lower esophageal sphincter relaxation and loss of esophageal peristalsis. Diagnosis is confirmed by clinical symptoms, endoscopic, radiographic and manometric. Although pneumatic dilation has a role in the treatment of achalasia, laparoscopic Heller myotomy is considered by many experts as the best treatment modality for most patients with newly diagnosed achalasia. Objective: To evaluate the efficacy and safety of laparoscopic Heller myotomy with Dor antireflux procedure. Patients and Methods: Prospective analyses of the patients of achalasia undergoing laparoscopic Heller myotomy with Dor antireflux procedure from 01/2012 to 06/2020. We evaluated the data according to outcome measures, characteristics and treatment results of achalasia after laparoscopic Heller myotomy with Dor antireflux procedure. Results: We found 11 patients with achalasia were diagnosed and treated by laparoscopic. 100% of the patients have dysphagia, weight loss; 81.8% have chest pain and regurgitation. Mean operative duration was 148 ± 21 minutes. There was no complications had found in our patients. Follow-up after 3 - 6 months by Eckardt score show that 90.9% had a good result, 01 patient with persistent symtomps (Eckardt score > 3) had to undergo a pneumatic dilation. Conclusion: The results of the laparoscopic Heller myotomy with Dor antireflux procedure were safe and effective. Keywwords: Achalasia, laparoscopic Heller myotomy, Dor antireflux procedure

In the context of global adaptation to climate change, the demandfor water, especially drinking water, becomes a serious issue that needs to be studied to find feasible and economical solutions. Many available technologies have been applied to produce drinking water such as filtration of groundwater or seawater. However, the implementation of these technologies is feasible or not depending on specific nature as well as socio-economic conditions. For the drought regions where there is no seawater and lack of groundwater, moisture separation technology becomesafeasible solution. A system to extract the water from moisture has been designed, fabricated and installed to provide 10 litersof drinking water per day. As the system operates; it can produce around 2.1 litersof drinking water per hour; and consume 1.8 kW of electricity. The system has been designed to be able to use two typesof power sources: one from solar energy (main source) and the other from the national grid (auxiliary source).

This study was focused on a new strategy by investigating whether the novel Ti0.7Mo0.3O2 material can be used as a conductive support for PtRu to prevent carbon corrosion and improve catalyst activity as the novel Ti0.7Mo0.3O2 support has some functional advantages. The 30 wt% PtRu/Ti0.7Mo0.3O2 catalyst showed the highest current density at the complete potential, which is approximately 12-fold and 1.4-fold higher than that of the commercial 20 wt% Pt/C (E-TEK) and 30 wt% PtRu/C (JM) catalysts, respectively, at 0.6 V (NHE) toward the methanol oxidation (MOR). Our data suggest that this enhancement is a result of the electronic Pt structure change upon its synergistic interaction with Ti0.7Mo0.3O2 support and the improved mass transport kinetics of PtRu/Ti0.7Mo0.3O2 compared to the carbon support (Pt or PtRu). The PtRu/Ti0.7Mo0.3O2 catalyst exhibited a much higher stability than carbon-supported catalysts because of the strong metal/support interactions between the Pt particles and Ti0.7Mo0.3O2, the inherent structural and chemical stability, and the corrosion resistance of the Ti0.7Mo0.3O2 in acidic and oxidative environments.

Absract Selenium nanoparticles (SeNPs) with diameter of ∼74 nm were synthesized by gamma Co-60 ray irradiation of H2SeO3/dextran solution. The SeNPs were characterized by UV–Vis spectroscopy spectrum and transmission electron microscope (TEM) images. The effect of pH of H2SeO3/dextran solutions before gamma irradiation on the size of SeNPs was investigated. The SeNPs/dextran powder was also prepared by spray drying technique and the purity was verified by energy dispersive X-ray (EDX) analysis. The ATBS•+ radical scavenging ability and reducing power of SeNPs were assessed. Results showed that SeNPs/dextran with concentration of 25–100 ppm exhibited high antioxidant activity. The as-prepared SeNPs/dextran powder with selenium content of ∼2.51% (wt%) was of high purity. The influence of gamma Co-60 ray sterilization at dose of 25 kGy on the characteristics of SeNPs/dextran powder was also examined.

In this study, the effect of salinity on the removal of organic matter and nitrogen concentrations in bioreactor was investigated using a hybrid bench scale down-flow hanging sponge (DHS) system for 145 days of operation. The reactor had three identical sections that were filled to 30% volume with Bio-Bact to serve as attached media. The DHS reactor was fed with domestic wastewater that was mixed with increasing concentration of sodium chloride from 0.5 to 3.0% stepwise. The influent and effluent concentrations of BOD5, CODCr, NH4+-N, and TN were analyzed to evaluate the performance of the DHS reactor during the operational period. Results indicate that when salinity was increased from 0.5 to 3.0%, the removal efficiency gradually decreased from 80.3% to 61.5% for CODCr, 76.4%–65.0% for BOD5, 64.1%–48.4% for NH4+-N, and 50%–36% for TN. Besides, the changes in biofilm characteristics with increasing salinity were observed during the operational period. The results indicate that salinity has a significant influence on the removal of organic matters and nitrogen transformation in the biofilm of the bioreactor. Even so, the DHS reactor revealed a good potential for treating saline wastewater.

Economic feasibility is one of the major factors that has to be considered in the decision to continue with alternative fuel development. Economic feasibility of these alternatives can be assessed through life cycle costing, which is dependent on volatile parameters such as feedstock price, operating rate, capacity, interest rate and conversion efficiency. Uncertainty analysis is necessary to determine the robustness of the life cycle cost estimates. In this study, design of experiments was demonstrated to be an effective approach to analyze the sensitivity of life cycle cost to these parameters. Furthermore, the sensitivity analysis can be done based not only on the individual effects, but also on the interactions of parameters. Data from the biodiesel program of Vietnam were used as a case study. The results show that operating cost and feedstock price have the most significant effects on biodiesel cost followed by capacity, interest rate and conversion efficiency. Interactions were observed between conversion efficiency and feedstock price; interest rate and operating rate; and feedstock price and interest rate. The regression equation obtained from sensitivity analysis shows that the cost of jatropha biodiesel is 0.72–1.02 US$/L, the cost of fish oil biodiesel is 0.45–0.87 US$/L, and the cost of waste cooking oil biodiesel is 0.42–0.61 US$/L. Although the framework developed in this study was used specifically in the life cycle costing of biodiesel, it can be readily applied to other low-carbon energy systems in the future.

Biodiesel has been widely proposed as an alternative to fossil fuels and its environmental impacts have been commonly assessed using life cycle assessment (LCA). However, the results of LCA can be affected by parameter uncertainties. The rigorous treatment of such uncertainties is thus essential to improve decision-making based on the LCA. In this work, the Latin hypercube design of experiments (DOE) approach is proposed for global sensitivity analysis in LCA. In this novel approach, the LCA input parameters are used as the factors for the experimental design. The LCA of biodiesel from different feedstocks, namely, jatropha, waste cooking oil (WCO), and fish oil (FO), under the current conditions in Vietnam was chosen as a test case. The LCA focuses on the global warming potential (GWP), photochemical ozone formation potential (POFP), acidification potential (AP), and eutrophication potential (EP) of the biodiesel system. These impact categories were then combined into an overall environmental impact (OEI) score using the analytic hierarchy process (AHP). The effect of changes in the LCA model parameters on the OEI was then observed through computational experiments using a Latin hypercube design. From the computational experiments, the input parameters significantly affecting the results of LCA were identified, and a proxy polynomial regression model was derived to enable global sensitivity analysis to be performed. The results show that agricultural yield, oil content of jatropha seed, transesterification yield, total transportation, and biodiesel blending fraction are the factors that have significant effects on the OEI of jatropha biodiesel; biodiesel blend fraction and total transportation are significant in the case of WCO diesel, while the only significant effect factor in FO biodiesel case is biodiesel blend fraction. Biodiesel blend fraction is the most significant parameter for all feedstocks.

Leaking underground petroleum storage poses human and environmental health risks as it contaminates the soil and the groundwater. Of the many contaminants, benzene – a major constituent of gasoline, is of primary concern. It is an identified carcinogen with a permissible limit set at a low level of 0.005 mg L−1. This poses technical and regulatory challenge to remediation of contaminated sites. Various specialized treatment methods are available, but despite of the high removal efficiencies of sophisticated treatments, the residual level still poses health risks. Thus, additional alternative ways that are cost effective and require minimum technical expertise are necessary, and a constructed wetland (CW) is a potential alternative. This study evaluates the performance of a surface flow type CW for the removal of benzene from the contaminated water. It further determines the efficacy of a common reed plant Phragmites karka in treating benzene. Planted and unplanted CW were acclimated with benzene for 16 wk and tested for an 8-d hydraulic retention time at benzene levels of 66 and 45 mg L−1. Results indicate that the planted CW performed better and gave reliable and stable results.

In this study, the chemical compositions, antioxidant and antimicrobial activities of essential oils (EOs) of different citrus varieties in Vietnam including LongAn lime, DaLat lime, Xoan orange, Vinh orange, TanTrieu pomelo and ThanhTra pomelo were investigated. Nine main volatile components including α-pinene (0.33-1.74 %), sabinene (0.15-2.54 %), β-pinene (0.02-14.58 %), myrcene (0.96-41.95 %), α-terpinene (0.08-0.42 %), limonene (40.29-95.78 %), terpinolene (0.02-0.57 %), γ-terpinene (0.02-12.14 %) and linalool (0.04-0.43 %) were found in the EOs of all citrus varieties as analyzed by GC-MS. The chemical compositions of EOs of two orange varieties were not significantly different, whereas those of lime and pomelo varieties varied depending on the varieties and growing locations. The EO of LongAn lime showed the highest antioxidant capacity, whereas the EO of Xoan orange had the lowest antioxidant capacity. All citrus EOs were exhibited high antimicrobial activities against the food-pathogenic ...

This study was focused on a new strategy by investigating whether the novel Ti0.7Mo0.3O2 material can be used as a conductive support for PtRu to prevent carbon corrosion and improve catalyst activity as the novel Ti0.7Mo0.3O2 support has some functional advantages. The 30 wt% PtRu/Ti0.7Mo0.3O2 catalyst showed the highest current density at the complete potential, which is approximately 12-fold and 1.4-fold higher than that of the commercial 20 wt% Pt/C (E-TEK) and 30 wt% PtRu/C (JM) catalysts, respectively, at 0.6 V (NHE) toward the methanol oxidation (MOR). Our data suggest that this enhancement is a result of the electronic Pt structure change upon its synergistic interaction with Ti0.7Mo0.3O2 support and the improved mass transport kinetics of PtRu/Ti0.7Mo0.3O2 compared to the carbon support (Pt or PtRu). The PtRu/Ti0.7Mo0.3O2 catalyst exhibited a much higher stability than carbon-supported catalysts because of the strong metal/support interactions between the Pt particles and Ti0.7Mo0.3O2, the inherent structural and chemical stability, and the corrosion resistance of the Ti0.7Mo0.3O2 in acidic and oxidative environments.